Cam, Rocker, & Rocker Shaft Initial Evaluation

2jmotorsports · 2jmotorsports's Garage

First time rebuilder here and I have fully disassembled my 200K mile 83 3.0L.

Below are my cams, rockers, and rocker shafts. The rockers and shafts all look like the 2 shown here.

Cams all have smooth and shiny lobes with no scratches or pits. The lobes are shinier at the highest points on the lobes. Also the journals do show scratch lines but they are ever so slightly detectable with a fingernail.

Rocker pads are also smooth and shiny but do also show a color change with the outer edges in a gold color and the center area a "silver" color.

Rocker shafts also smooth and shiny but show spots of color change in some areas. The rocker bushings also have similar spots of color change but all look smooth.

I dont have any paperwork on this engine. Only was told it had a top end rebuild at 150K miles but I cant verify that.

What is your first impression of the health of these parts? Do they seem re-usable? My current plan is a stock rebuild (US spec) and retain the stock CIS.

Thanks in advance.

mreid · 05-07-2016, 07:29 AM

Those color changes are heat induced, but normal with that mileage. Do you know which cam lobe each rocker belongs to? I would have them conditioned and rebushed. The cams look fine in the limited pictures.

2jmotorsports · 2jmotorsports's Garage

I do. All rockers and shafts are individually labelled. Ill get some more photos today in better lighting.

If I have the rockers reconditioned (refaced) do I need to replace the cams or is that only when getting new rockers so they wear evenly together?

2jmotorsports · 2jmotorsports's Garage

More cam photos out in daylight.

2jmotorsports · 2jmotorsports's Garage

It looks like there are a few very small nicks on the lobe surfaces after all. These are the largest.

Gene Smith · Gene Smith's Garage

I had similar "pitting" on my '69 S cams and John Doughtery repaired them for me. He also sold me refurbished rockers and rocker shafts. I am very pleased with the work and turnaround.

2jmotorsports · 2jmotorsports's Garage

Awesome. Thanks for the input. Im going to shelve and get everything reconditioned once I get to the top end portion of my rebuild.

Gene Smith · Gene Smith's Garage

I think that is smart. Then you will have fresh everything. Be sure to check the cam-lube spray tubes are clear. Mine had a blockage that created the damage on one lobe. Good Luck!

KTL · 05-10-2016, 08:59 AM

That brown on the non-contact areas of the rocker pads and shafts doesn't look heat related. I think that's oil staining.

DRACO A5OG · DRACO A5OG's Garage

Quote:

Originally Posted by 2jmotorsports

Awesome. Thanks for the input. Im going to shelve and get everything reconditioned once I get to the top end portion of my rebuild.

Hey Jose,

So did you end up sending the rockers and shafts to DRC?

Planning on send mine in for him to refurb.

Jim

2jmotorsports · 2jmotorsports's Garage

Jim,

Not yet. Still on the bottom end portion of my rebuild. About to send my case, crank, and rods out to the machine shop.

This one is going to go slow and in stages to make it fit the budget and schedule.

3literpwr · 05-25-2016, 07:33 PM

Send your rockers to Craig! He's fast and priced right.

theiceman · 05-26-2016, 06:25 AM

Quote:

Originally Posted by KTL

That brown on the non-contact areas of the rocker pads and shafts doesn't look heat related. I think that's oil staining.

when I did mine I rotated the rocker shafts 180 degrees when I put them back.

DRACO A5OG · DRACO A5OG's Garage

Quote:

Originally Posted by theiceman

when I did mine I rotated the rocker shafts 180 degrees when I put them back.

Hmmm, I was thinking of doing that as well but I will have DRC evaluate the shafts and the adjustment screw pads for abnormal wear and replace if needed.

theiceman · 05-26-2016, 10:57 AM

Quote:

Originally Posted by DRACO A5OG

Hmmm, I was thinking of doing that as well but I will have DRC evaluate the shafts and the adjustment screw pads for abnormal wear and replace if needed.

ill forget I did this and on the next rebuild I will have screwed myself

tharbert · tharbert's Garage

Shafts are only $15 new. That's probably about the same as postage and DRC's labor to even pick a shaft up from the table. Just sayin'...

DRACO A5OG · DRACO A5OG's Garage

True that and the ends will not be so stretched out :-)

Ultrafast993 · 05-26-2016, 05:28 PM

What oil are you using?

DRACO A5OG · DRACO A5OG's Garage

If the question is directed to me, I will be using Valvoline VR1 20W50 with the Wix Filter (Napa Gold) for the first 5 minute Start at 2000RPMs. I will be cranking without spark or fuel for the first 10-12 cranks to build up the oil pressure on the tensioners and insure all is oiled up properly. Even before that, hand crank at least 6 times. Better safe then sorry

I have the Wix filters laying around and figured I will sacrifice those. Wix filters too well but will be happy to use it to get any little dirt/metal microns out of the car for the remaining break in periods.

After initial 5 minutes, back to Mahle Filters.

KTL · 05-27-2016, 07:05 AM

Take a look at the installation specs (new) and the clearance spec for the shafts. It's TIGHT.

0.035mm new clearance is 0.0014" Wear limit of 0.080mm is three thousandths of an inch

So I think most shafts showing strong visible wear will be out of spec. even with new bushings. That said, they are just a bit noisy with larger clearance. They're not going to fail.

But it's a lot like the chain and sprocket. Replacing one without the other doesn't result in a good fit and returns you back to wear condition quite quickly